Friction speed-gear for automobiles.



W. E. TRUFANT. FBIOTIOH SPEED GEAR FOB AUTOMOBILES.

APPLIOATIOI FILED TBL, 1000.

Patented Doo 24, 1912.

WALTER E. TRUFANT, OFWHITHAN, MASSACHUSETTS.

FRIIOTION SPEED-GEAR FOB AUTOMOBILES.

Bpeoication of Letten Patent.

Patented Dec. 24, 1912.

Application tiled February 28, 1906. Serial No. 802,830.

To all 'whom it may concern:

Be it known that I, WALTER E. TnUFANr of Whitman, in the countlym1 ofPlymouth and State of Massachusetts, ave invented certain new and usefulImprovements in Frictiun S eed-Gear for Automobiles, of which the foowing is a s ecification.

This invention re ates to speed changing and power transmittin gearingfor automobi es, and in many eatures is intended as an improvement overpatent for frictiondrive speed-gear, No. 805,504, dated Nov. 28, 1905,granted to me; and consists in such form and arrangement of the frictiondisks as to relieve their journals froml excessive thrust strains and beeasily operated, and in various other features which will be hereinafterdescribed and particularly pointed out in the claims.

In the embodiment of my invention shown in the accompanying drawingsforming a part of this s ecification, Figure 1 shows a plan lar ly insection, of my invention applied to t e regular styile of automobile,and i 2 shows gearing aving a transmitting dis on opposite sides of theroll and driving shaft, and Fig. 3 is another view of the saine.

In Fig. 1 a represents the frame of the machine and b the engine shaftwhich may be supplied with power from an suitable source. On the en 'neshaft is eyed the hub or clutch case b this hub is practicall anenlargement of the engine or ower sha t and carries the balance wheeland also the power transmittin friction wheel b' made to slide freelyaxia ly on the hub. The friction wheel is slid on the hub by means ofthe lever b pivoted at b, and the end of this lever is normally in thenotch b in the shifter b. This shifter is operated by the hand bar b'.The power delivering surface of the friction wheel may be faced withleather or other friction material as shown at b. The hub b* is splinedout on opposite sides internally to take the pro'ecting ears on thealternate clutch disks an is recessed to fit loosely the bearin ease o".The transmitting friction disk is journaled to the frame at d with itspower delivering surface parallel with the shaft c and its beveled owerreceiving surface parallel with the riction surface of the wheel b. Thedisk d is normally held against the journal box d and out of contactwith all friction surfaces by the helical spring d. Power is a plied tothe disk d by the friction wheel di and transmitted by the disk to theroll c1, which is provided with the friction rim c, to the driving shaftc. Power is transmitted from the shaft c through the universal 'oints ce, propeller shaft e e, joints e e, evel gears 1 to the shaft or axle l.This shaft l may be either a countershaft for chain drive 0r the vehicleaxle itself. Propeller shafts which run to the axle must be providedwith a slip joint to permit the action of the springs of the vehicle,and it is desirable to have some torsional flexibility between theengine and theroad wheels for if one or both wheels are suddenlyaccelerated or retarded by the vehicle passing over rough surfaces thestrains set up are very great and result in broken engine shafts andstripped ears. I provide against these shaft strains y makin thepropeller shaft iiexiblc so that all o the strains are taken up withoutdanger to the other arts of the transmission. The propeller s aft ismade of one or more flat, wide strips or bars e el, which may be ofmetal, wood or other material. These are fitted loosel in the slots inthe back end e of the for of the universal joint and are held in placeby the collar e. This makes a cheap connection and a good slip joint,and in case of breakage of the propeller bars a new one may be put in bysimply slipping oil' the collar and sliding in the new bar and re lacingthe collar.

In o eration whi e the vehicle is standingr the di clutch is released,so when the enine is started the onl parts rotated will the hub b withthe riction wheel b and the clutch disks. The roll c1 is then slid b vmeans of the bar c and shipper c, a T shaped piece sliding in lugs inthe side of the frame and imparting the movement of the bar o to theroll c, to a osition, as shown in Fig. 2, just forward of) the center ofthe disk d and the shifter b" is then moved by the notched piece b1o sothat the lever b is held in the notch b.wlien thc friction wheel b' isslid on its ke Way against the beveled face of the disk I which thenrevolves at the saine surface speed as the wheel. A further movement ofthe wheel ba carries in the disk d, against the action of the spring d,and forces it against the periphery of the roll o1` which will'.revolve` atl the same surface speed as the part. ofthe disk with whichit is in contact. This gives the slowest forward speed. The roll maythen be moved forward along the face of ,the disk increasing the speedas it ap roaches the edge of the disk. It will be noticed that as thefriction wheel b is pressed against the disk d the disk is automaticallyraised into contact with the roll c by the wedge shaped arrangement ofthe surfaces and if there is slippage between any of the frictionsurfaces further pressure on the wheel by the shipper b willautomaticall increase the ressure alike on all the sur aces. To get t ereverso the roll is moved toward the rear edge of the disk as shown bythe dotted lines in Fi 1. As the roll approaches the forward e ge of thedisk the trip arm cl1 coines in contact with the shifter at b and throwsit out of engagement with the lever b" and the point c pushes the leveralong carrying the friction wheel out of contact with the disk d whichis drawn by the spring d away from the roll cl and against the 'ournalbox d* when the disk comes to rest.

he same movement which throws out the disk as just described brings thecone c in contact with the clutch arms and thus clam is the clutchmembers to ether and all of t ie parts turn as one and t e drive isdirect with none of the friction drive surfaces in contact. In Fig. 1the parts are all shown in direct drive position. It will be noticedthat when the friction disk is drivin the vehicle there is no thruststrain on the Ibearing d and, owing to the angle of the contact surfacesalmost none on the friction wheel and lever b.

Figs. 2 and 3 show a modification of the construction shown in Fig. 1and said modification luis two disks opposite each other which thusbalance the strain on the bearings of all the frictional surfaces due tothe force required to secure the proper driving contact and gives apropelling force on opposite sides of the friction roll. In thesefigures g is the friction wheel and li a rock shaft carrying two rolls ih which bear on the back of the friction disk opposite the point wherethe Contact is made with the friction disks and thus regulates theressure on the beveled friction surfaces o the disks z' il and on theroll 7'.

,What I`clamas new, and desire to secure by Letters Patent of the UnitedStates, is-

,1. In an4 apparatus of the kind described the combination of, a. powershaft, a wheel `having ,a friction surface on said power shaft, adisk'having two friction surfaces, one. of saidsurfaces being adapted tobe brought in'contact with the friction surface on said wheel,'a drivingshaft, and a roll on said driving shaft, the said friction sui-- facesbeing shaped to automatically regulate the ressure on said surfaces whensaid wliee and disk are in contact.

2. In an apparatus of the kind described the combination of, a powershaft, a driving shaft, a clutch to connect said power shaft and saiddriving shaft, an internally beveled friction wheel on said power shaft,a beveled friction disk to receive power from said wheel, and a roll onsaid driving shaft to receive power from said disk.

3. In an apparatus of the kind described the combination of, a powershaft, a wheel having a friction surface on said power shaft, a diskhaving two friction surfaces, one of said surfaces being ada )ted to bebrought in contact with the friction surface on said wheel, a drivingshaft, and a roll on said driving shaft, the said friction surfacesbeing shaped to automatically regulate thc pressure on said surfaceswhen said wheel and disk are in contact, and means to con nect saidpower shaft and driving shaft together.

4. In an apparatus of the kind described the combination of, a powershaft, an inwardly beveled disk on said power shaft, a disk having anoutwardly beveled surface and a. flat surface, the outwardly beveledsurface of said disk being ada ted to be brought in contact with thebeve ed surface of said inwardly beveled disk, a driving shaft, and aroll on said driving shaft', the said friction surfaces being shaped toantomatically regulate the ressure on said surfaces when said bevelc(surfaces are in contact.

In testimony whereof I have affixed my signature, in the presence of twowitnesses.

\VALTER E. TRUFANT.

Witnesses: I

ItosANNa CALLANAN G. HOWARD SoULE.

Copies of this patent may be obtained for ave cents each, by addressingthe "Commissioner of Patents. Washington, D. C."

